awr报告没有数据11.2.0.3

有个朋友，反馈AWR没有数据；

咨询版本：oracle企业版本11.2.0.3

SQL>  select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE    11.2.0.3.0      Production
TNS for Linux: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production

SQL>  show parameter STATISTICS_LEVEL;

NAME                                 TYPE                             VALUE
------------------------------------ -------------------------------- ------------------------------
statistics_level                     string                           TYPICAL

观察统计信息收集，无异常

再观察，参数

SQL> show parameter control_management_pack_access

NAME                                 TYPE                             VALUE
------------------------------------ -------------------------------- ------------------------------
control_management_pack_access       string                           NONE

 根据MOS搜索可以发现，当db版本处于11.1.0.6-11.2.0.3，默认情况下，生成快照但是没有awr信息，可以修改参数输出awr信息，也可以禁用。

AWR Snapshots get Generated After Setting CONTROL_MANAGEMENT_PACK_ACCESS=NONE (Doc ID 1437539.1) 
Oracle Database - Enterprise Edition - Version 11.1.0.6 to 11.2.0.3 [Release 11.1 to 11.2]

For Database versions 11g or later, the parameter CONTROL_MANAGMENT_PACK_ACCESS is implemented to control the AWR license. 
When the parameter CONTROL_MANAGMENT_PACK_ACCESS is set to NONE, it is expected behavior that
AWR snapshots will continue to be generated. However, metrics will not be generated.

DETAILS
Even though CONTROL_MANAGMENT_PACK_ACCESS is set to NONE, AWR snapshots still get generated.
This is expected behavior. The snapshots will get generated, but metrics will not be collected during this period. 
Once the value is set to DIAGNOSTIC+TUNING, then it will start collecting metrics.
In order to disable AWR snapshots, a call to modify the snapshot settings needs to to be executed using the following:
exec dbms_workload_repository.modify_snapshot_settings(interval=>0);